Yaron Hellman

B-Type Natriuretic Peptide-Guided Therapy and Length of Hospital Stay Post Left Ventricular Assist Device Implantation

B-type natriuretic peptide (BNP)-guided therapy during the early postoperative period following left ventricular assist device (LVAD) implantation has not been well described in the literature. We conducted a retrospective cohort study consisting of consecutive patients who underwent LVAD implantation at our institution during May 2009 to March 2013. The study was limited to patients receiving HeartMate II (Thoratec) or HVAD (HeartWare) LVADs. Patients with acute myocardial infarction were excluded. We compared between patients with multiple postoperative BNP tests (BNP-guided therapy) and earlier period patients who typically had only a baseline BNP measurement (non-BNP-guided therapy). A total of 85 patients underwent LVAD implantation during the study period. Eight patients were excluded (five acute myocardial infarction, three without BNP measurements). The only differences in the baseline characteristics of BNP versus non-BNP-guided therapy included age and female gender. The postoperative length of hospital stay (LOS) in the BNP-guided therapy group was 5 days shorter when compared with the non-BNP-guided therapy group. In multivariate analysis, BNP-guided therapy remained a significant predictor of reduced LOS. The use of repeated BNP measurements during the early postoperative period was associated with a significantly lower LOS post LVAD implantation.

Pulse Oximeter Derived Blood Pressure Measurement in Patients With a Continuous Flow Left Ventricular Assist Device

Currently, blood pressure (BP) measurement is obtained noninvasively in patients with continuous flow left ventricular assist device (LVAD) by placing a Doppler probe over the brachial or radial artery with inflation and deflation of a manual BP cuff. We hypothesized that replacing the Doppler probe with a finger-based pulse oximeter can yield BP measurements similar to the Doppler derived mean arterial pressure (MAP). We conducted a prospective study consisting of patients with contemporary continuous flow LVADs. In a small pilot phase I inpatient study, we compared direct arterial line measurements with an automated blood pressure (ABP) cuff, Doppler and pulse oximeter derived MAP. Our main phase II study included LVAD outpatients with a comparison between Doppler, ABP, and pulse oximeter derived MAP. A total of five phase I and 36 phase II patients were recruited during February-June 2014. In phase I, the average MAP measured by pulse oximeter was closer to arterial line MAP rather than Doppler (P = 0.06) or ABP (P < 0.01). In phase II, pulse oximeter MAP (96.6 mm Hg) was significantly closer to Doppler MAP (96.5 mm Hg) when compared to ABP (82.1 mm Hg) (P = 0.0001). Pulse oximeter derived blood pressure measurement may be as reliable as Doppler in patients with continuous flow LVADs.

B‐Type Natriuretic Peptide Levels Predict Ventricular Arrhythmia Post Left Ventricular Assist Device Implantation

B-type natriuretic peptide (BNP) levels have been shown to predict ventricular arrhythmia (VA) and sudden death in patients with heart failure. We sought to determine whether BNP levels before left ventricular assist device (LVAD) implantation can predict VA post LVAD implantation in advanced heart failure patients. We conducted a retrospective study consisting of patients who underwent LVAD implantation in our institution during the period of May 2009-March 2013. The study was limited to patients receiving a HeartMate II or HeartWare LVAD. Acute myocardial infarction patients were excluded. We compared between the patients who developed VA within 15 days post LVAD implantation to the patients without VA. A total of 85 patients underwent LVAD implantation during the study period. Eleven patients were excluded (five acute MI, four without BNP measurements, and two discharged earlier than 13 days post LVAD implantation). The incidence of VA was 31%, with 91% ventricular tachycardia (VT) and 9% ventricular fibrillation. BNP remained the single most powerful predictor of VA even after adjustment for other borderline significant factors in a multivariate logistic regression model (P < 0.05). BNP levels are a strong predictor of VA post LVAD implantation, surpassing previously described risk factors such as age and VT in the past.

A prescribed walking regimen plus arginine supplementation improves function and quality of life for patients with pulmonary arterial hypertension: A pilot study

Current evidence suggests that exercise training is beneficial in pulmonary arterial hypertension (PAH). Unfortunately, the standard supervised, hospital-based programs limit patient accessibility to this important intervention. Our proof-of-concept study aimed to provide insight into the usefulness of a prescribed walking regimen along with arginine supplementation to improve outcomes for patients with PAH. Twelve PAH patients (all women) in New York Heart Association (NYHA) functional class (FC) II (n = 7) or III (n = 5) and in stable condition for ≥ 3 months were enrolled. Patients performed home- and fitness-center- based walking at 65–75% heart rate (HR) reserve for 45 min, six sessions/week for 12 weeks. Concomitant L-arginine supplementation (6000 mg/day) was provided to maximize beneficial endothelial training adaptations. Cardiopulmonary exercise testing, 6-min walk testing (6MWT), echocardiography, laboratory studies, and quality of life (QoL) survey (SF-36) were performed at baseline and 12 weeks. Eleven patients completed the study (72 session adherence rate = 96 ± 3%). Objective improvement was demonstrated by the 6MWT distance (increased by 40 ± 13 m, P = 0.01), VO2max (increased by 2 ± 0.7 mL/kg/min, P = 0.02), time-to-VO2max (increased by 2.5 ± 0.6 min, P = 0.001), VO2 at anaerobic threshold (increased by 1.3 ± 0.5 mL/kg/min, P = 0.04), HR recovery (reduced by 68 ± 23% in slope, P = 0.01), and SF-36 subscales of Physical Functioning and Energy/Fatigue (increased by 70 ± 34% and 74 ± 34%, respectively, P < 0.05). No adverse events occurred, and right ventricular function and brain natriuretic peptide levels remained stable, suggesting safety of the intervention. This proof-of-concept study indicates that a simple walking regimen with arginine supplementation is a safe and efficacious intervention for clinically stable PAH patients, with gains in objective function and QoL measures. Further investigation in a randomized controlled trial is warranted.

B-TYPE NATRIURETIC PEPTIDE LEVELS PREDICT VENTRICULAR ARRHYTHMIA POST LEFT VENTRICULAR ASSIST DEVICE IMPLANTATION

B Type Natriuretic Peptide (BNP) levels have been shown to predict Ventricular Arrhythmia (VA) and sudden death in heart failure. We sought to determine whether BNP can predict VA post Left Ventricular Assist Device (LVAD) implantation. We conducted a retrospective nested case-control study